It is difficult to say which is better, BITS Pilani or IIT Roorkee, as they are both highly respected institutions in India. Both universities have strong programs in engineering, technology, and science.
However, BITS Pilani is known for its focus on undergraduate education, while IT Roorkee is known for its research programs. Yet if I was to choose one, I would have chosen BITS Pilani for BTech
However, if you are someone who is interested in MTech in core branches or is inclined towards research work, then IIT Roorkee has a better research culture. Moreover, the extremely high fees at BITS Pilani might be a demotivating factor for many making IIT Roorkee a much better choice.